I am trying to write a program that stops with a specific string input

Question

I am just starting to learn C coding ,I am trying to write a program that keeps scanning names and once it scans a specific name lets say for example "John" it stops Please correct me

#include <stdio.h>
int main()
{
    char name[20];
    printf("enter a name:");
    for(;;)
    {
        scanf("%s",name);
        if (name='John')
        {
            break;
        }

    }

First of all, you are not comparing `name` to "John", you are assigning it. And second, using the `==` operator on two string pointers is not going to compare the contents of the strings. — jkb, Jun 24 '21 at 23:27
You already asked this exact [same question](https://stackoverflow.com/questions/68123015/need-help-in-c-to-stop-the-loop-once-you-input-a-specific-name) today (now deleted). And you have already been pointed to the duplicate post that shows you the correct way to compare strings. Why are you asking the same question again and why are you not acting on the info already given to you? — kaylum, Jun 24 '21 at 23:31
it is either `int main(void)` or `int main(int argc, char **argv)`. Don't use `"%s"` with `scanf`. At least give a max length: `"%19s"`. `'John'` is an integer of implementation defined value, not a string. `"John"` is a string. `=` is assignment, not the comparison operator `==`. But then `==` doesn't say if to strings are equal, only if they are stored in the same memory location. Use `strcmp` for string comparison. And always compile with `-Wall`. The compiler could then have told you some of this. — HAL9000, Jun 25 '21 at 00:47

score 0 · Accepted Answer · answered Jun 24 '21 at 23:32

0

You can't compare two string pointers with != or ==. you need to use strcmp, for example:

while (strcmp(check,input) != 0)

strcmp compares the string pointed to, by str1 to the string pointed to by str2.

answered Jun 24 '21 at 23:32

Amir Basic

16

`strcmp` is right but `while` is not in the context of the code in the question. – kaylum Jun 24 '21 at 23:34
This is just one example, with the proviso that while could be used in his case as well, as he wants the program to scan all names until it reaches "John" – Amir Basic Jun 24 '21 at 23:37
But `input` is not changing @Amir! – Ajay Brahmakshatriya Jun 25 '21 at 01:25

I am trying to write a program that stops with a specific string input

1 Answers1